What to Expect in the Goldman Sachs System Design Interview

Goldman Sachs gives experienced engineering candidates one dedicated system design interview, usually at the Superday. It runs about 45 to 60 minutes with a Goldman engineer. The questions tie to the firm's own systems: trading, market data, risk, and banking. Reported examples include designing a real-time trading platform and designing a risk monitoring system that reads data from multiple exchanges.

Entry-level candidates get little or no design. Mid-level and senior candidates should treat this round as a deciding one. A strong design round often sets the level of the offer.

The Format

The round is a conversation at a whiteboard or a shared drawing tool. The interviewer gives a broad problem with missing details on purpose. You are expected to ask questions, state requirements, estimate scale, draw the parts, and defend your trade-offs.

Interviewers at Goldman push on failure cases. Expect questions like: what happens when this feed stops, and who notices first? Budget your time: about five minutes for requirements, ten for the high-level picture, and the rest for depth.

The Question Types Goldman Asks

• Market-facing systems. Design a real-time trading platform, an order management system, or a price feed handler. The pressure point is latency: the delay between an event and your system's response.
• Risk and monitoring systems. Design a system that computes exposure (how much money is at stake) across many positions, or monitors data from several exchanges. The pressure point is correctness under constant change.
• Data and platform systems. Design a reporting pipeline, a reference data service, or an internal API platform. The pressure point is scale and clean contracts between teams.
• General classics. Some interviewers ask standard questions: a URL shortener, a notification service, a rate limiter. Practice these too.

A Worked Example: Risk Monitoring Across Exchanges

Here is a high-level path through the reported risk monitoring question.

Requirements. Ingest trade and price feeds from several exchanges. Keep a current exposure number per trading desk. Alert a human within about one second when a limit is passed. Keep history for audit.

Scale. Assume tens of thousands of messages per second at peak. Assume a few thousand desks and instruments. Numbers this size rule out a single database doing everything.

Core design. Each exchange feed lands in a message queue (a buffer that stores events until a consumer reads them). A stream processor reads the queues and updates positions per desk. Current exposure lives in an in-memory store for fast reads. A separate writer saves every event to a time-series database (a database organized around timestamps) for audit and replay.

Alerting. A rules service checks exposure against limits on every update. Alerts go to a queue of their own, so a slow email system never delays detection.

The trade-offs to say out loud. Exact global correctness and one-second alerts fight each other. Say that you favor fast, slightly stale alerts, backed by an exact end-of-day reconciliation. Handle a dead feed by marking its data stale and alerting on staleness itself.

What Interviewers Evaluate

• Requirements first. Strong candidates spend the first five minutes asking questions and naming constraints: latency, throughput, storage, and failure behavior.
• Trade-off reasoning. There is no correct architecture. There are defended choices. Every component you add should answer a stated requirement.
• Failure thinking. Finance systems are judged on their worst day. Volunteer the failure story before the interviewer asks.
• Communication. Goldman engineers work next to the business. Clear, plain explanations of technical choices are part of the score.

How to Prepare

• Learn the building blocks cold. Queues, caches, sharding, replication, and consistency come up in every finance design. Grokking the System Design Interview teaches them through complete worked designs.
• Go deeper for senior loops. Stream processing, exactly-once delivery, and multi-region trade-offs get direct questions at senior level. Grokking the Advanced System Design Interview handles that layer.
• Practice two finance designs end to end. Do a trading platform and a risk monitor, out loud, with a timer at 45 minutes. Both reported Goldman questions live in this space.
• Know the rest of the loop. The design round sits inside a larger Superday. See What is the Goldman Sachs interview process like? and Top Goldman Sachs behavioral interview questions.